package com.tianji.learning.service.impl;

import com.tianji.common.autoconfigure.mq.RabbitMqHelper;
import com.tianji.common.constants.MqConstants;
import com.tianji.common.exceptions.BizIllegalException;
import com.tianji.common.utils.CollUtils;
import com.tianji.common.utils.UserContext;
import com.tianji.learning.constants.RedisConstants;
import com.tianji.learning.domain.vo.SignResultVO;
import com.tianji.learning.mq.msg.SignInMessage;
import com.tianji.learning.service.ISignRecordService;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.List;

/**
 * @Description
 * @Author lyx
 * @since 2025/1/28 14:55
 */
@Service
@Slf4j
@RequiredArgsConstructor
public class SignRecordServiceImpl implements ISignRecordService {

    private final StringRedisTemplate redisTemplate;
    private final RabbitMqHelper mqHelper;

    /**
     * 签到功能
     * @return
     */
    @Override
    public SignResultVO addSignRecords() {
        //1.获取用户id
        Long userId = UserContext.getUser();
        //2.拼接key
        LocalDate now = LocalDate.now();//当前时间的年月
        String format = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = RedisConstants.SIGN_RECORD_KEY_PREFIX + userId.toString() + format;

        //3.利用bitset命令 将签到记录保存到redis的bitmap中  需要校验是否已签到
        int offset = now.getDayOfMonth() - 1;//偏移量
        Boolean setBit = redisTemplate.opsForValue().setBit(key, offset, true);
        if (setBit){
            //说明已经签过到
            throw new BizIllegalException("不能重复签到");
        }

        //4.计算连续签到天数
        int days = countSignDays(key,now.getDayOfMonth());

        //5.计算连续签到  奖励积分
        int rewardPoints = 0;
        switch (days) {
            case 7:
                rewardPoints = 10;
                break;
            case 14:
                rewardPoints = 20;
                break;
            case 28:
                rewardPoints = 40;
                break;
        }

        //6.保存积分 发送消息到mq
        mqHelper.send(MqConstants.Exchange.LEARNING_EXCHANGE,
                MqConstants.Key.SIGN_IN,
                SignInMessage.of(userId,rewardPoints+1));

        //7.封装vo返回
        SignResultVO vo = new SignResultVO();
        vo.setSignDays(days);
        vo.setRewardPoints(rewardPoints);
        return vo;
    }


    /**
     * 计算连续签到多少天
     * @param key 缓存中的key
     * @param dayOfMonth 本月第一天到今天的天数
     * @return
     */
    private int countSignDays(String key, int dayOfMonth) {
        //1.求本月第一天到今天所有的签到数据 得到是十进制
        //bitfiled key get u天数 0
        List<Long> bitField = redisTemplate.opsForValue().bitField(key,
                BitFieldSubCommands.create()
                        .get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0));
        if (CollUtils.isEmpty(bitField)){
            return 0;
        }
        Long num = bitField.get(0);//拿到是十进制
        log.debug("num  {}",num);

        //2.num 转 二进制 从后往前推有多少个1 与运算 右移
        int counter = 0; //计数器
        while ((num & 1) == 1){
            counter++;
            num = num>>>1; //右移1位
        }
        return counter;
    }

    /**
     * 查询签到记录
     * @return
     */
    @Override
    public Byte[] querySignRecords() {
        //1.获取用户id
        Long userId = UserContext.getUser();

        //2.拼接key
        LocalDate now = LocalDate.now();//当前时间的年月
        String format = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = RedisConstants.SIGN_RECORD_KEY_PREFIX + userId.toString() + format;

        //3.利用redis bitfield命令取本月第一天到今天所有的签到记录
        int dayOfMonth = now.getDayOfMonth();
        List<Long> bitField = redisTemplate.opsForValue().bitField(key,
                BitFieldSubCommands.create().get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth)).valueAt(0));
        if (CollUtils.isEmpty(bitField)){
            return new Byte[0];
        }
        Long num = bitField.get(0);
        int offset = dayOfMonth - 1;

        //4.利用与运算和 位移 封装结构
        Byte[] arr = new Byte[dayOfMonth];
        while (offset >= 0){
            arr[offset] = (byte)(num & 1);//计算最后一天是否签到 赋值结果
            offset--;
            num = num>>>1; //右移
        }
        return arr;
    }

}
